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1.
BMC Infect Dis ; 20(1): 16, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31910816

RESUMO

BACKGROUND: Cryptosporidium is a genus of common intestinal protozoa, members of which cause diarrhea in a wide variety of hosts. Previous studies on Cryptosporidium in China have mainly focused on diarrhea sufferers, children, and immunodeficient individuals such as HIV/AIDS patients. However, the epidemiological characteristics of Cryptosporidium in the population in rural areas remain unclear. Herein, we investigated the prevalence of, and risk factors for, Cryptosporidium in rural areas of Binyang County, Guangxi Zhuang Autonomous Region, China, and genetically characterized the Cryptosporidium isolates we obtained. METHODS: From August to December 2016, two villages in Binyang County, Guangxi, were sampled using a random cluster sampling method. Fresh fecal samples were collected from all eligible residents (residence time > 6 months). Molecular characterization of Cryptosporidium was carried out based on its SSU rRNA, gp60, actin and hsp70 gene sequences. Fisher's exact test were conducted to assess the risk factors for Cryptosporidium infection. RESULTS: A total of 400 fecal samples were collected from 195 males (48.8%) and 205 females (51.2%). Two samples (0.5%) were positive for Cryptosporidium and were identified as C. viatorum and C. occultus respectively. Moreover, a new C. viatorum subtype XVaA3h was identified based on the sequence of the gp 60 gene. CONCLUSIONS: To our knowledge, this is the first report of C. viatorum and C. occultus infections in humans in China and of C. viatorum subtype XVaA3h. The findings provide important information on the prevalence of Cryptosporidium in the Chinese population, and expand the range of Cryptosporidium species known to infect people in China.


Assuntos
Sequência de Bases/genética , Criptosporidiose/epidemiologia , Cryptosporidium/classificação , Cryptosporidium/genética , DNA de Protozoário/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Pré-Escolar , China/epidemiologia , Estudos Transversais , Criptosporidiose/parasitologia , Cryptosporidium/isolamento & purificação , Diarreia/parasitologia , Fezes/parasitologia , Feminino , Genótipo , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Filogenia , Prevalência , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
2.
Parasit Vectors ; 12(1): 510, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31666095

RESUMO

BACKGROUND: Apicomplexan parasites of the genus Cryptosporidium infect a wide range of animal species as well as humans. Cryptosporidium spp. can cause life threatening diarrhea especially in young animals, children, immunocompromised patients and malnourished individuals. Asymptomatic cryptosporidial infections in animals can also occur, making these animals potential reservoirs of infection. METHODS: In the present study, a molecular survey of Cryptosporidium spp. in ruminants that were slaughtered for human consumption in Yazd Province, located in central Iran was conducted. Faeces were collected per-rectum from 484 animals including 192 cattle, 192 sheep and 100 goats. DNA was extracted from all samples and screened for Cryptosporidium by PCR amplification of the 18S rRNA gene. Positives were Sanger sequenced and further subtyped by sequence analysis of the 60 kDa glycoprotein (gp60) locus. RESULTS: In total, Cryptosporidium spp. were detected in 22 animals: C. andersoni and C. bovis in seven and two cattle faecal samples, respectively, C. ubiquitum in five sheep, and C. xiaoi in six sheep and two goat samples, respectively. To our knowledge, this study provides for the first time, molecular information concerning Cryptosporidium species infecting goats in Iran, and is also the first report of C. ubiquitum and C. xiaoi from ruminants in Iran. CONCLUSION: The presence of potentially zoonotic species of Cryptosporidium in ruminants in this region may suggest that livestock could potentially contribute to human cryptosporidiosis, in particular among farmers and slaughterhouse workers, in the area. Further molecular studies on local human populations are required to more accurately understand the epidemiology and transmission dynamics of Cryptosporidium spp. in this region.


Assuntos
Criptosporidiose/enzimologia , Criptosporidiose/parasitologia , Cryptosporidium/classificação , Fatores Etários , Animais , Bovinos , Criptosporidiose/epidemiologia , Cryptosporidium/genética , DNA de Protozoário/isolamento & purificação , Reservatórios de Doenças/parasitologia , Fezes/parasitologia , Técnicas de Genotipagem , Cabras , Humanos , Hospedeiro Imunocomprometido , Irã (Geográfico)/epidemiologia , Desnutrição/complicações , Prevalência , RNA Ribossômico 18S/genética , Ovinos , Zoonoses/parasitologia
3.
Parasitol Res ; 118(12): 3429-3441, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31667591

RESUMO

The parasite Cryptosporidium parvum Tyzzer 1912 destroys parts of the intestinal brush border membrane which is important for the uptake of nutrients like glucose. In this study, glucose transport mechanisms of the host cells (IPEC-J2 cells) infected by C. parvum were investigated. The mRNA expression levels of glucose transporters (GLUT) 1 and 2 and Na+-coupled glucose transporter (SGLT) 1 were compared in infected and uninfected cells over an infection time of 24-96 h by RT-qPCR. Furthermore, the protein expression of SGLT 1 and GLUT 2 was quantified in western blot studies. While the protein expression of SGLT 1 was not altered in infected cells, mRNA expression of SGLT 1 and GLUT 1 was significantly increased 24 h p. i. and decreased 96 h p. i. The mRNA expression of GLUT 2 was significantly decreased 24 h, 72 h, and 96 h p. i. and also correlated significantly with the infection dose at 72 h p. i. In contrast to that, the protein expression of GLUT 2 was significantly increased 48 h p. i., associated with a significantly higher intracellular glucose level in infected cells compared with control cells at that time point of infection. This points to an adaptation of the host cells' glucose uptake taking place in the acute phase of the infection. A better understanding of these molecular mechanisms following a C. parvum infection may probably lead to an improvement of therapy strategies in the future.


Assuntos
Criptosporidiose/patologia , Cryptosporidium parvum/metabolismo , Enterócitos/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Transportador 1 de Glucose-Sódio/metabolismo , Animais , Transporte Biológico , Linhagem Celular , Criptosporidiose/parasitologia , Enterócitos/parasitologia , Glucose/metabolismo , Suínos
4.
Parasitol Res ; 118(12): 3555-3559, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31722067

RESUMO

The aim of this study was to survey the Cryptosporidium species in peafowls (Pavo cristatus) in Henan Province, China. A total of 143 fecal specimens collected from a breeding farm were tested for Cryptosporidium by nested PCR targeting the small subunit rRNA (SSU rRNA), 70-kDa heat shock protein (HSP70), and actin genes of Cryptosporidium followed by sequence analysis. Only one isolate from an asymptomatic host was obtained, and the isolate differed from a new C. xiaoi-like genotype by one nucleotide and from C. xiaoi or C. bovis at the SSU rRNA locus by six nucleotides. Likewise, the actin gene shared 99% identity with the C. xiaoi-like genotype, accompanied by four nucleotide mutations. A complete sequence of the HSP70 gene was obtained, and exhibited 96% similarity with that from C. xiaoi and differed by one nucleotide from that with the C. xiaoi-like genotype. Phylogenetic analysis of the current isolate revealed genetic relatedness to the C. xiaoi-like genotype and distinction from C. xiaoi and C. bovis. Therefore, our results provided the first documentation of avian infection with a C. xiaoi-like genotype in China and further insight into the diversity of Cryptosporidium spp. in avians.


Assuntos
Doenças das Aves/parasitologia , Criptosporidiose/parasitologia , Cryptosporidium/isolamento & purificação , Animais , Doenças das Aves/epidemiologia , China/epidemiologia , Criptosporidiose/epidemiologia , Cryptosporidium/classificação , Cryptosporidium/genética , DNA de Protozoário/genética , Fezes/parasitologia , Galliformes/parasitologia , Genótipo , Filogenia , Reação em Cadeia da Polimerase/veterinária , RNA Ribossômico/genética
5.
Parasitol Res ; 118(12): 3195-3204, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31724068

RESUMO

Whole genomic sequencing (WGS) and comparative genomics are increasingly used in the characterization of Cryptosporidium spp. They are facilitated by the establishment of procedures for WGS analysis of clinical specimens without laboratory propagation of pathogens. Results of recent comparative genomics analysis suggest that gene duplication might be associated with broad host ranges of some zoonotic Cryptosporidium species and subtypes, while genetic recombination could be involved in the emergence of virulent subtypes. The availability of WGS data has further facilitated the development of advanced molecular typing tools. The use of these tools together with comparative genomics analyses has begun to improve the investigations of outbreaks in industrialized nations. More WGS data, however, are needed from both industrialized nations and developing countries before we can have in-depth understanding of the population genetics and evolution of Cryptosporidium spp. and genetic determinants of various phenotypic traits in human-pathogenic subtypes.


Assuntos
Criptosporidiose/epidemiologia , Cryptosporidium/genética , Genômica , Animais , Criptosporidiose/parasitologia , Criptosporidiose/transmissão , Cryptosporidium/classificação , Cryptosporidium/patogenicidade , Genoma de Protozoário/genética , Genótipo , Especificidade de Hospedeiro/genética , Humanos , Epidemiologia Molecular , Virulência/genética
6.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 31(5): 474-478, 2019 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-31713374

RESUMO

OBJECTIVE: To investigate the prevalence and molecular features of Cryptosporidium in sheep and goats from Anhui Province and neighboring provinces. METHODS: A total 832 and 781 fresh fecal samples were collected from seven large-scale sheep farms and ten large-scale goat farms in Anhui Province and neighboring provinces of Henan, Jiangsu and Shandong. The prevalence and species of Cryptosporidium were investigated in the fecal samples from the sheep and goats in the study areas using nested PCR assay based on the Cryptosporidium-specific SSU rDNA gene, and the subgenotypes of C. parvum and C. ubiquitum were characterized by amplification and sequencing of the 60 kDa glycoprotein (gp60) gene. RESULTS: The overall prevalence of Cryptosporidium was 5.8% (48/832) in sheep and 8.7% (68/781) in goats in Anhui Province and neighboring provinces, respectively. The SSU rDNA gene-based PCR assay identified C. xiaoi and C. ubiquitum in sheep and C. parvum in goats, and subtyping revealed that all C. ubiquitum subgenotypes belonged to XIIa subtype 2 and C. parvum subgenotypes belonged to IIdA19G1. CONCLUSIONS: The identification of zoonotic C. ubiquitum XIIa subtype 2 and C. parvum subtype IIdA19G1 suggests that sheep and goats may serve as a potential source for human Cryptosporidium infections.


Assuntos
Criptosporidiose , Cryptosporidium , Doenças das Cabras , Doenças dos Ovinos , Animais , Criptosporidiose/epidemiologia , Criptosporidiose/parasitologia , Cryptosporidium/classificação , Cryptosporidium/genética , Fezes/parasitologia , Genótipo , Doenças das Cabras/epidemiologia , Doenças das Cabras/parasitologia , Cabras , Humanos , Reação em Cadeia da Polimerase , Prevalência , RNA Ribossômico 18S/genética , Ovinos , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/parasitologia
7.
Parasit Vectors ; 12(1): 502, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31661007

RESUMO

BACKGROUND: Cryptosporidium viatorum is a minor Cryptosporidium pathogen in humans. Currently, there is limited information regarding the prevalence and genotypes of C. viatorum in animals in China. METHODS: In this study, 228 faecal samples were collected from two wild rat species (Leopoldamys edwardsi and Berylmys bowersi) in Chongqing Municipality and Guangdong Province, China. These specimens were analyzed for C. viatorum and then subtyped it using PCR and sequence analysis of the small subunit ribosomal RNA (SSU rRNA) and 60-kilodalton glycoprotein (gp60) genes, respectively. RESULTS: A total of 25 (11.0%) faecal samples were tested positive for C. viatorum by SSU rRNA assay. Of these samples, 4 (3.6%) came from L. edwardsi and 21 (18.0%) from B. bowersi. Of the 25 C. viatorum-positive samples, 17 were successfully amplified at the gp60 gene locus, which represented four subtypes belonging to two subtype families, including XVa (XVaA6, XVaA3g, XVaA3h) and XVc (XVcA2G1). Phylogenetic analysis based on the gp60 amino acid sequences indicated that all of the C. viatorum isolates grouped together, supporting the conclusion that C. viatorum from the wild rats represent two subtype families. CONCLUSIONS: These results indicate an occurrence of C. viatorum XVa subtype family from rats which is genetically identical to those found in humans. Our findings suggest that wild rats may be a potential source of human cryptosporidiosis.


Assuntos
Criptosporidiose/parasitologia , Cryptosporidium/isolamento & purificação , Murinae/parasitologia , Doenças dos Roedores/parasitologia , Sequência de Aminoácidos , Animais , China/epidemiologia , Criptosporidiose/epidemiologia , Criptosporidiose/transmissão , Cryptosporidium/classificação , Cryptosporidium/genética , DNA de Protozoário/genética , DNA de Protozoário/isolamento & purificação , Fezes/parasitologia , Humanos , Filogenia , Reação em Cadeia da Polimerase/veterinária , Prevalência , RNA Ribossômico/química , Doenças dos Roedores/epidemiologia , Doenças dos Roedores/transmissão , Sialoglicoproteínas/química , Sialoglicoproteínas/genética
8.
Parasitol Res ; 118(12): 3509-3517, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31624910

RESUMO

Cryptosporidium spp. and Giardia duodenalis are protozoan parasites that cause diarrhea in humans and animals. Molecular data on Cryptosporidium spp. and G. duodenalis in calves in the Republic of Korea (ROK) is limited; thus, we investigated the prevalence of Cryptosporidium and Giardia in pre-weaned calves, analyzed the association between these parasites and diarrhea, and identified their zoonotic potential for human infection. Fecal samples were collected from 315 pre-weaned calves aged 1-60 days from 10 different regions in the ROK and screened for Cryptosporidium spp. and G. duodenalis using PCR. Overall prevalence of Cryptosporidium spp. and G. duodenalis was 4.4% (n = 14) and 12.7% (n = 40), respectively. Co-infection was not detected. All Cryptosporidium-positive samples were identified as C. parvum after sequence analysis of a small subunit rRNA fragment and further subtyped into zoonotic IIaA15G2R1 (n = 13) and IIaA18G3R1 (n = 1) by DNA sequencing of the 60-kDa glycoprotein gene. To our knowledge, this is the first report of C. parvum IIaA15G2R1 subtype in calves in the ROK. Based on ß-giardin (bg) gene, G. duodenalis-positive samples belonged to assemblages E (n = 36) and A (n = 4), with the latter belonging to subtype A1, the zoonotic genotype. Six subtypes of assemblage E were identified at the bg locus: E1 (n = 6), E2 (n = 3), E3 (n = 13), E5 (n = 1), E8 (n = 1), and E11 (n = 1). The occurrence of C. parvum and G. duodenalis was not associated with diarrhea in pre-weaned Korean native calves. The present results suggest that the prevalence of C. parvum is not related to calf age; in contrast, the prevalence of G. duodenalis was significantly higher in 41-50-day-old calves (odds ratio = 9.90, 95% confidence interval 2.37-41.34; P = 0.001) than in 1-10-day-old calves. Therefore, calves are a potential source of zoonotic transmission, which may have significant public health implications.


Assuntos
Doenças dos Bovinos/parasitologia , Criptosporidiose/parasitologia , Cryptosporidium/genética , Cryptosporidium/isolamento & purificação , Giardia/genética , Giardíase/veterinária , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/fisiopatologia , Criptosporidiose/epidemiologia , Criptosporidiose/fisiopatologia , Cryptosporidium/classificação , Fezes/parasitologia , Feminino , Genótipo , Giardia/classificação , Giardia/isolamento & purificação , Giardíase/epidemiologia , Giardíase/parasitologia , Giardíase/fisiopatologia , Masculino , Reação em Cadeia da Polimerase , Prevalência , República da Coreia/epidemiologia , Desmame
9.
Ann Parasitol ; 65(3): 237-243, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31599539

RESUMO

Rabbits are commonly reared by households and farmers in Nigeria as a source of meat, but there is no information available on Cryptosporidium genotypes occurring in rabbits in Nigeria. Fecal samples were collected from 107 rabbits and examined by modified Ziehl-Neelsen technique for the presence of Cryptosporidium oocysts. An infection rate of 3.7% (4/107) was obtained and all microscopy-positive samples were genotyped and subtyped to determine the circulating Cryptosporidium species using sequence analysis of the 18S rRNA gene and 60-kDa glycoprotein (gp60) gene, respectively. All the four microscopy-positive samples were identified as C. parvum by 18S rRNA gene. However, analysis of the gp60 gene revealed the presence of C. parvum subtype IIc, which is commonly found in humans in two isolates. These findings indicate natural infection of rabbits with C. parvum and underscore the need to investigate the probable role of animal hosts in the epidemiology of Cryptosporidium infection. This is the first report on genetic characterization of Cryptosporidium infecting rabbits in Nigeria.


Assuntos
Criptosporidiose , Cryptosporidium parvum , Doenças Parasitárias em Animais , Animais , Criptosporidiose/diagnóstico , Criptosporidiose/epidemiologia , Criptosporidiose/parasitologia , Cryptosporidium parvum/genética , Fezes/parasitologia , Genótipo , Humanos , Nigéria/epidemiologia , Doenças Parasitárias em Animais/diagnóstico , Doenças Parasitárias em Animais/epidemiologia , Doenças Parasitárias em Animais/parasitologia , Reação em Cadeia da Polimerase , RNA Ribossômico 18S/genética , Coelhos , Análise de Sequência de DNA , Sialoglicoproteínas/genética
10.
BMC Infect Dis ; 19(1): 808, 2019 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-31521133

RESUMO

BACKGROUND: Enterocytozoon bieneusi and Cryptosporidium spp. are prevalent zoonotic parasites associated with a high burden among children. To date only limited molecular epidemiological data on E. bieneusi and Cryptosporidium spp. in humans living in Thailand has been published. METHODS: PCR-based tools were used to detect and characterize E. bieneusi and Cryptosporidium spp. The internal transcribed spacer (ITS) region of the rRNA gene was used to investigate E. bieneusi, and the small subunit (SSU) rRNA gene was used to investigate Cryptosporidium spp., and 697 fecal samples from villagers and school children in rural areas in Thailand were analyzed. RESULTS: The infection rates were 2.15% (15/697) for E. bieneusi and 0.14% (1/697) for Cryptosporidium spp. The prevalence of E. bieneusi was significantly high in Loei province. Sequence analysis indicated that the Cryptosporidium isolate was C. parvum. Nine E. bieneusi genotypes were identified, EbpC, Peru12, TMH6, TMH3, TMH7, H, D, and two novel genotypes TMLH1 and TMLH2. E. bieneusi prevalence was significantly higher in male participants than in female participants, and in children aged 3-15 years than in participants aged > 15 years. CONCLUSIONS: The prevalence, genotypes, and zoonotic potential of E. bieneusi were found to vary significantly high even in one country. Transmission routes and key animal carriers of E. bieneusi may be associated with differences in hygiene, sanitation, and cultural behaviors. Further molecular studies including longitudinal studies will be required to unveil epidemiological characteristics of these opportunistic intestinal protozoa in all over the countries.


Assuntos
Criptosporidiose/epidemiologia , Cryptosporidium/classificação , Enterocytozoon/classificação , Microsporidiose/epidemiologia , Zoonoses/epidemiologia , Adolescente , Animais , Gatos , Criança , Pré-Escolar , Estudos Transversais , Criptosporidiose/parasitologia , Criptosporidiose/transmissão , Cryptosporidium/genética , Cryptosporidium/isolamento & purificação , Enterocytozoon/genética , Enterocytozoon/isolamento & purificação , Fezes/parasitologia , Feminino , Genótipo , Humanos , Higiene , Masculino , Microsporidiose/parasitologia , Microsporidiose/transmissão , Filogenia , Prevalência , População Rural , Saneamento , Suínos , Tailândia/epidemiologia , Zoonoses/transmissão
11.
Parasitol Res ; 118(11): 3159-3171, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31486948

RESUMO

Cryptosporidiosis is a significant cause of gastroenteritis in both humans and livestock in developing countries. The only FDA-approved drug available against the same is nitazoxanide, with questionable efficacy in malnourished children and immunocompromised patients. Recent in vitro studies have indicated the viability of Triacsin C as a potential drug candidate, which targets the parasite's long-chain fatty acyl coenzyme A synthetase enzyme (LC-FACS), a critical component of the fatty acid metabolism pathway. We have used this molecule as a baseline to propose more potent versions thereof. We have applied a combined approach of substructure replacement, literature search, and database screening to come up with 514 analogs of Triacsin C. A virtual screening protocol was carried out which lead us to identify a potential hit compound. This was further subjected to a 100-ns molecular dynamics simulation in complex to determine its stability and binding characteristics. After which, the ADME/tox properties were predicted to assess its viability as a drug. The molecule R134 was identified as the best hit due to its highest average binding affinity, stability in complex when subjected to MD simulations, and reasonable predicted ADMET (Absorption, Distribution, Metabolism, Excretion and Toxicity) properties comparable to those of the Triacsin C parent molecule. We have proposed R134 as a putative drug candidate against the Cryptosporidium parvum LC-FACS enzyme isoforms, following an in silico protocol. We hope the results will be helpful when planning future in vitro experiments for identifying drugs against Cryptosporidium.


Assuntos
Antiprotozoários/farmacologia , Coenzima A Ligases/antagonistas & inibidores , Cryptosporidium parvum/enzimologia , Cryptosporidium parvum/metabolismo , Descoberta de Drogas/métodos , Triazenos/farmacologia , Acil Coenzima A/metabolismo , Animais , Antiprotozoários/química , Criança , Criptosporidiose/tratamento farmacológico , Criptosporidiose/parasitologia , Ácidos Graxos/metabolismo , Gastroenterite/parasitologia , Humanos , Simulação de Dinâmica Molecular , Isoformas de Proteínas , Triazenos/química
12.
PLoS Negl Trop Dis ; 13(9): e0007411, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31560681

RESUMO

Based on our initial observations showing that mice consuming a probiotic product develop more severe cryptosporidiosis, we investigated the impact of other dietary interventions on the intracellular proliferation of Cryptosporidium parvum and C. tyzzeri in the mouse. Mice were orally infected with oocysts and parasite multiplication measured by quantifying fecal oocyst output. High-throughput sequencing of 16S ribosomal RNA amplicons was used to correlate oocyst output with diet and with the composition of the intestinal microbiota. On average, mice fed a diet without fiber (cellulose, pectin and inulin) developed more severe infections. As expected, a diet without fibers also significantly altered the fecal microbiota. Consistent with these observations, mice fed a prebiotic product sold for human consumption excreted significantly fewer oocysts. The fecal microbiota of mice consuming no plant polysaccharides was characterized by a lower relative abundance of Bacteroidetes bacteria. Since bacterial metabolites play an important role in the physiology of intestinal enterocytes, we hypothesize based on these observations that the impact of diet on parasite proliferation is mediated primarily by the metabolic activity of the anaerobic microbiota, specifically by the effect of certain metabolites on the host. This model is consistent with the metabolic dependence of intracellular stages of the parasite on the host cell. These observations underscore the potential of dietary interventions to alleviate the impact of cryptosporidiosis, particularly in infants at risk of recurrent enteric infections.


Assuntos
Criptosporidiose/metabolismo , Criptosporidiose/parasitologia , Fibras na Dieta/metabolismo , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Criptosporidiose/microbiologia , Cryptosporidium/fisiologia , Suscetibilidade a Doenças , Fezes/microbiologia , Fezes/parasitologia , Feminino , Microbioma Gastrointestinal , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL
13.
Vet Parasitol ; 273: 32-35, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31442890

RESUMO

This study looked to assess the stability of Cryptosporidium parvum genotypes in calves between the final day of treatment with the antiprotozoal halofuginone lactate and seven days post-treatment. Paired faecal samples were collected on the final day of treatment and seven days later from 54 calves across seven farms in South-west England. The presence of Cryptosporidium species was detected using polymerase chain reaction targeting the 18 s rDNA. The presence and genotype of C. parvum was determined by PCR and amplicon sequencing targeting the gp60 locus. On farms where C. parvum was detected at both sampling times there was a distinct genotype shift. Detection of gp60 genotype IIaA15G2R1 decreased from 40% to 7% while IIaA17G1R1 increased from 0% to 41%, supplemented by IIaA16G3R1 in one sample. A shift in C. parvum genotypes present in calves within a one week sampling timeframe has not been described prior to this study, indicating that the timeframe is likely suitable for observing variation in C. parvum populations and interactions with antiprotozoal control strategies.


Assuntos
Doenças dos Bovinos/parasitologia , Criptosporidiose/parasitologia , Cryptosporidium parvum/genética , Animais , Antiprotozoários/uso terapêutico , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Criptosporidiose/tratamento farmacológico , Inglaterra , Fezes/parasitologia , Genes de Protozoários/genética , Genótipo , RNA Ribossômico 18S/genética
14.
Vet Parasitol ; 273: 67-70, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31442896

RESUMO

Suckling calves are prone to Cryptosporidium infection. The variable degree of clinical disease is influenced by keeping conditions and immune status of the host, but diversity of isolate virulence may also contribute. The aim of the current study was to evaluate the cytopathogenic effects of 26 C. parvum field isolates by using a MTT assay in HCT-8 cell monolayers. Cell viability of monolayers inoculated with oocysts of the field isolates varied considerably with values of 17.7% (± 5.1%) to 99.5% (± 7.1%). A standard deviation of 18.6% was detected for cell viability of the in house reference strain, which were tested alongside in every assay. Field isolates were grouped in three categories of cytopathogenicity. Probably the length of storage has an effect on the level of the cell destruction category detected post infection in vitro. The applied tool may help to better understand the variable course of cryptosporidiosis in the field.


Assuntos
Doenças dos Bovinos/parasitologia , Criptosporidiose/parasitologia , Cryptosporidium parvum/patogenicidade , Animais , Bovinos , Linhagem Celular , Sobrevivência Celular , Células Epiteliais/citologia , Células Epiteliais/parasitologia , Interações Hospedeiro-Parasita/imunologia , Humanos , Virulência/imunologia
15.
BMC Public Health ; 19(1): 1144, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31429732

RESUMO

BACKGROUND: Cryptosporidiosis is a pathological condition caused by infection with coccidian protozoan parasites Cryptosporidium. Cryptosporidium is one of the most common causes of childhood diarrhea in developing countries. So far, no data has been published on its prevalence among children with diarrhea in Cameroon. This study was therefore, designed to assess the prevalence and risk factors associated with Cryptosporidiosis among children within the ages 0-5 years suffering from diarrhea and being attended to at the Limbe Regional Hospital. METHODS: The study was a hospital based analytical cross-sectional study involving children within the ages 0-5 years (n = 112) hospitalized or consulted in the pediatric departments of the hospital between April 2018 and May 2018. Stool specimens were processed using the modified acid-fast staining method, and microscopically examined for Cryptosporidium infection. RESULTS: A total of 112 participants were recruited out of which 67 presented with diarrhea. A high prevalence 9/67 (13.40%) of Cryptosporidium was noticed in children with diarrhea than children without diarrhea 1/45 (2.2%). There was a significant relationship (p = 0.041) between prevalence of Cryptosporidium and the presence of diarrhea in children within the ages 0-5 years in the Limbe Regional Hospital. It was realized that children from parents with primary level of education, children whose parents did not respect exclusive breastfeeding and those whose parents were giving them pipe borne water for drinking recorded a higher prevalence. CONCLUSIONS: This study revealed an overall prevalence of 8.9% for Cryptosporidium among children of ages 0-5 years that attended the Limbe Regional Hospital. The prevalence among children that presented with diarrhea was 13.4%. The study clearly demonstrated that Cryptosporidium is an important protozoal etiologic agent for children with diarrhea in Limbe.


Assuntos
Criptosporidiose/epidemiologia , Cryptosporidium , Diarreia/parasitologia , Animais , Aleitamento Materno/estatística & dados numéricos , Camarões/epidemiologia , Pré-Escolar , Estudos Transversais , Criptosporidiose/parasitologia , Países em Desenvolvimento , Escolaridade , Feminino , Hospitais/estatística & dados numéricos , Humanos , Lactente , Recém-Nascido , Masculino , Pais , Prevalência , Fatores de Risco
16.
PLoS Pathog ; 15(7): e1007953, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31356619

RESUMO

Cryptosporidium parvum is a highly prevalent zoonotic and anthroponotic protozoan parasite that causes a diarrheal syndrome in children and neonatal livestock, culminating in growth retardation and mortalities. Despite the high prevalence of C. parvum, there are no fully effective and safe drugs for treating infections, and there is no vaccine. We have previously reported that the bacterial-like C. parvum lactate dehydrogenase (CpLDH) enzyme is essential for survival, virulence and growth of C. parvum in vitro and in vivo. In the present study, we screened compound libraries and identified inhibitors against the enzymatic activity of recombinant CpLDH protein in vitro. We tested the inhibitors for anti-Cryptosporidium effect using in vitro infection assays of HCT-8 cells monolayers and identified compounds NSC158011 and NSC10447 that inhibited the proliferation of intracellular C. parvum in vitro, with IC50 values of 14.88 and 72.65 µM, respectively. At doses tolerable in mice, we found that both NSC158011 and NSC10447 consistently significantly reduced the shedding of C. parvum oocysts in infected immunocompromised mice's feces, and prevented intestinal villous atrophy as well as mucosal erosion due to C. parvum. Together, our findings have unveiled promising anti-Cryptosporidium drug candidates that can be explored further for the development of the much needed novel therapeutic agents against C. parvum infections.


Assuntos
Antiprotozoários/farmacologia , Cryptosporidium parvum/efeitos dos fármacos , Cryptosporidium parvum/enzimologia , Inibidores Enzimáticos/farmacologia , L-Lactato Desidrogenase/antagonistas & inibidores , Proteínas de Protozoários/antagonistas & inibidores , Animais , Linhagem Celular , Criptosporidiose/tratamento farmacológico , Criptosporidiose/parasitologia , Criptosporidiose/patologia , Cryptosporidium parvum/patogenicidade , Interações Hospedeiro-Parasita/efeitos dos fármacos , Humanos , L-Lactato Desidrogenase/química , L-Lactato Desidrogenase/genética , Camundongos , Camundongos Knockout , Simulação de Acoplamento Molecular , Testes de Sensibilidade Parasitária , Proteínas de Protozoários/química , Proteínas de Protozoários/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética
17.
Zoonoses Public Health ; 66(7): 813-825, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31305029

RESUMO

There are few epidemiologic studies on the role of dogs in zoonotic parasitic transmission in the Circumpolar North. The objectives of this study were to: (a) estimate the faecal prevalence of Giardia spp. and Cryptosporidium spp. in dogs; (b) investigate potential associations between the type of dog population and the faecal presence of Giardia spp. and Cryptosporidium spp.; and (c) describe the molecular characteristics of Giardia spp. and Cryptosporidium spp. in dogs in Iqaluit, Nunavut. We conducted two cross-sectional studies in July and September 2016. In July, the team collected daily faecal samples for 3 days from each of 20 sled dogs. In September, the team collected three faecal samples from each of 59 sled dogs, 111 samples from shelter dogs and 104 from community dogs. We analysed faecal samples for the presence of Giardia spp. and Cryptosporidium spp. using rapid immunoassay and flotation techniques. Polymerase chain reaction (PCR) and sequencing of target genes were performed on positive faecal samples. Overall, the faecal prevalence of at least one of the target parasites, when one faecal sample was chosen at random for all dogs, was 8.16% (CI: 5.52-11.92), and for Giardia spp. and Cryptosporidium spp., prevalence was 4.42% (CI: 2.58-7.49) and 6.12% (CI: 3.88-9.53), respectively. The odds of faecal Giardia spp. in sled dogs were significantly higher than those in shelter and community dogs (OR 10.19 [CI: 1.16-89.35]). Sequence analysis revealed that 6 faecal samples were Giardia intestinalis, zoonotic assemblage B (n = 2) and species-specific assemblages D (n = 3) and E (n = 1), and five faecal samples were Cryptosporidium canis. Giardia intestinalis is zoonotic; however, Cryptosporidium canis is rare in humans and, when present, usually occurs in immunosuppressed individuals. Dogs may be a potential source of zoonotic Giardia intestinalis assemblage B infections in residents in Iqaluit, Nunavut, Canada; however, the direction of transmission is unclear.


Assuntos
Criptosporidiose/parasitologia , Cryptosporidium/isolamento & purificação , Doenças do Cão/parasitologia , Giardia/isolamento & purificação , Giardíase/veterinária , Animais , Criptosporidiose/epidemiologia , Cryptosporidium/classificação , Doenças do Cão/epidemiologia , Cães , Fezes/parasitologia , Giardia/classificação , Giardíase/epidemiologia , Giardíase/parasitologia , Nunavut , Fatores de Tempo
18.
Rev Inst Med Trop Sao Paulo ; 61: e28, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31241657

RESUMO

Cryptosporidium spp. is a pathogenic protozoan present in the gastrointestinal tract of several hosts. This protozoan was originally classified as within the Coccidia Class and has recently been reclassified to gregarine based on studies that observed the evolutionary phases from the process of excision and sequencing of the 18S rRNA gene. Molecular biology techniques have become diagnostic tools and have also been used to understand the epidemiology of Cryptosporidium spp., since several species of this genus are very similar morphologically and morphometrically. Molecular techniques have been used in the identification of parasites, at the species and subtypes levels and to study disease transmission. The laboratory diagnosis of human cryptosporidiosis can be made by parasite detection methods, such as optical microscopy, antigens or genetic material detection, as well as serum antibodies raised to Cryptosporidium spp. Molecular methods were developed and allowed, not only an extensive revision of the taxonomy, but also an improvement in the laboratory diagnosis. In Brazil, there are few reports of Cryptosporidium spp. outbreaks in humans and all of them took place in nurseries. A few epidemiological studies developed in Brazil have used molecular methods for the detection of Cryptosporidium spp., as well as genotyping studies of their species and subtypes. The use of real-time PCR, together with microscopy and immunochromatography techniques, would result in a more precise diagnosis of cryptosporidiosis. The analysis of genotypes, subtypes and clonality of Cryptosporidium could be useful to understand and define the prognosis and severity of infections.


Assuntos
Criptosporidiose/parasitologia , Cryptosporidium/genética , Cryptosporidium/isolamento & purificação , DNA de Protozoário/genética , Fezes/parasitologia , Animais , Brasil/epidemiologia , Criptosporidiose/diagnóstico , Criptosporidiose/epidemiologia , Cryptosporidium/classificação , DNA de Protozoário/análise , Genótipo , Humanos , RNA Ribossômico/genética , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA
19.
Cell Host Microbe ; 26(1): 123-134.e8, 2019 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-31231046

RESUMO

Despite being a frequent cause of severe diarrheal disease in infants and an opportunistic infection in immunocompromised patients, Cryptosporidium research has lagged due to a lack of facile experimental methods. Here, we describe a platform for complete life cycle development and long-term growth of C. parvum in vitro using "air-liquid interface" (ALI) cultures derived from intestinal epithelial stem cells. Transcriptomic profiling revealed that differentiating epithelial cells grown under ALI conditions undergo profound changes in metabolism and development that enable completion of the parasite life cycle in vitro. ALI cultures support parasite expansion > 100-fold and generate viable oocysts that are transmissible in vitro and to mice, causing infection and animal death. Transgenic parasite lines created using CRISPR/Cas9 were used to complete a genetic cross in vitro, demonstrating Mendelian segregation of chromosomes during meiosis. ALI culture provides an accessible model that will enable innovative studies into Cryptosporidium biology and host interactions.


Assuntos
Criptosporidiose/patologia , Criptosporidiose/parasitologia , Cryptosporidium/patogenicidade , Células Epiteliais/parasitologia , Interações Hospedeiro-Patógeno , Modelos Teóricos , Animais , Células Cultivadas , Cryptosporidium/crescimento & desenvolvimento , Genética Microbiana/métodos , Camundongos Endogâmicos C57BL , Técnicas Microbiológicas/métodos
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